A warehouse in Al Quoz, known as the ‘spa’ for luxury cars, charges as much as Dh7,000 and takes up to four days for each car to achieve the perfect clean.

The shop, a franchise of a German company called Select Nano, has catered to owners of Bugatti Veyrons, Aston Martins, and most recently an Audi R8 GT, one of only 333 produced worldwide.

Half of the cars brought there are worth more than Dh1 million and most are new.

For Sami Messayeh, spending Dh4,000 on a single car wash makes perfect sense. He does it twice a year for each of his four vehicles.

A British car lover and construction executive, Mr. Messayeh, 51, belongs to a small clientele in Dubai who believe luxury cars require luxury care.

Mr. Messayeh, like other customers, took his vehicles straight from the showroom to the warehouse to achieve what the maker did not: the mirror effect, a glossiness so great that he can see himself in it; and the pearl effect, a protective layer so glassy that water simply beads off.

The secret, say the two men who run Select Nano, is nanotechnology that fills in every microscopic dent on the car.

“When you look at it with a magnifying glass you can see, it is so clear, the difference.”

The treatment protects against what the Select Nano business developer Frederik Faidhi, 49, a British-born Iraqi, describes as the natural and man-made horrors inflicted on cars in Dubai.

From the dust and humidity to the “contaminated” water used at car washes that leaves behind salts and minerals, lesser car washes just aren’t going to cut it for these luxury vehicles.

And don’t get Mr. Messayeh started on scrubbing, which he says spreads the residue left by the water and breaks the protective coating on the car.

Also left behind are the cleaning streaks that can be seen from certain angles and are known, to those who care, as “holograms”.

“I am one of these people who does not believe that an exotic or luxury car should be washed by Tom, Dick or Harry,” Mr Faidhi says.

The cars at Select Nano are washed by a “chief polisher” using de-ionised water and a special microfibre cloth. The cloth must not be applied in swirl motions, but with a “throw and pull”, which Mr Faidhi demonstrates with his arms and fingertips as though teaching a ballet move.

That’s just the first step.

The car is then inspected and the granular imperfections marked on a set of drawings that show the vehicle from every side. Then it is cleaned with several products that are sometimes left to set overnight.

Next it receives an anti-hologram polish, an alcohol dilution and a protective coating or two – or more.

At each stage, Mr Faidhi scrutinises the work of the polisher, a young man from Bangladesh named Mujeeb, who had a few years of car-wash experience before joining Select Nano, where he was given several months of training by a representative from Germany.

“I’ve had employees and I’ve made them cry,” Mr Faidhi says. “The result has to be 100 per cent; 98 per cent is not acceptable. If I find mistakes, the client will find them.”

He grew up around fancy cars. His father ran a garage in an upscale neighbourhood in London.

During the tennis championships at Wimbledon, near his family’s home, the young Mr Faidhi would rent parking space on their property for £15 a day – twice that for a wash, and thrice for a wash and polish.

He met his business partner, the recent Emirati graduate Khalifa Al Shamsi, 27, and they discovered a mutual obsession with cars. They both knew what a hologram was.

Mr Al Shamsi had discovered Select Nano on the internet in 2007 and spent two years negotiating for a franchise, setting up the workshop and being trained by the company. He opened the shop in 2009 and recently recruited Mr Faidhi.

Mr Al Shamsi likes the idea of making brand new vehicles even more beautiful.

“It’s a piece of art,” he says. “They have done everything perfectly and it’s our challenge to make it more perfect.”

Tarek Jreigy, 39, a Lebanese businessman, recently became a believer.

Like other customers, Mr Jreigy had been paying about Dh2,000 at other shops. But after taking his new Maserati Quattroporte to Select Nano once, he signed a Dh10,000 contract for a full year of care.

“It was exactly what I was expecting,” he says, adding he will take his Audi R8 convertible in next.